Garage Sensor

Arduino Parking Assistant

An Arduino-based parking assistant that uses an ultrasonic sensor to measure your car's distance from a wall or obstacle. Based on the measured distance, it lights up one of three LEDs (green, yellow, red) to help you park safely and accurately.

Features

• Ultrasonic distance measurement using HC-SR04 sensor
• Three-level LED indication:
  • Green LED: Safe distance
  • Yellow LED: Getting close
  • Red LED: Stop!
• Automatic timeout: LEDs turn off after 30 seconds of inactivity

Installation Instructions

***CODE IS ON GITHUB***

1. Install Arduino IDE

• Download the Arduino IDE for your operating system.
• Follow the installation instructions for Windows, macOS, or Linux.
• Connect your Arduino board to your computer via USB.

2. Set Up the Project

• Clone or download this Repository from Github.
• Open main.cpp in the Arduino IDE.
• Select your Arduino board and port from the Tools menu.
• Click Upload to flash the code to your Arduino.

Hardware Required

• 1 × Arduino Uno (or compatible) $16.17 USD
• 1 × HC-SR04 Ultrasonic Sensor $4.63 USD
• 3 × LEDs (Red, Yellow, Green) $6.09 USD
• 3 × 220Ω resistors $0.1 USD
• Jumper wires $0.1 USD
• Breadboard $3 USD

Total = $30.09 USD

Schematic Diagram

Below is a schematic diagram showing how to wire the components:

[HC-SR04]      [Arduino UNO] VCC    ------> 5V GND    ------> GND TRIG   ------> Pin 9 ECHO   ------> Pin 10 [LEDs] Green  ------> Pin 2 (with 220Ω resistor to GND) Yellow ------> Pin 3 (with 220Ω resistor to GND) Red    ------> Pin 4 (with 220Ω resistor to GND)

Distance Calculation

The HC-SR04 ultrasonic sensor measures distance by sending out an ultrasonic pulse and timing how long it takes to receive the echo. The distance is calculated using the formula:

distance in cm = duration * 0.034(The speed of sound) / 2

• duration is the time of pulse
• 0.034 isnt the speed of sound, The speed of sound is 343 m/s but we want the distance in cm to I lowered the decimal places
• Divide by 2 Because we only want one way time.
• The sensor emits a pulse via the TRIG pin.
• The ECHO pin goes HIGH for the duration it takes the pulse to travel to the object and back.
   

Usage 

• As you approach the sensor, the LEDs indicate your distance:
  • Green: Far (safe)
  • Yellow: Getting close
  • Red: Very close (stop)
• If the distance category changes, the corresponding LED lights up.
• If no change is detected for 30 seconds, all LEDs turn off automatically.